Cell integrity signaling activation in response to hyperosmotic shock in yeast.

Current progress highlights the role of the yeast cell wall as a highly dynamic structure that responds to many environmental stresses. Here, we show that hyperosmotic shock transiently activates the PKC signaling pathway, a response that requires previous activation of the HOG pathway. Phosphorylation of Slt2p under such conditions is related to changes in the glycerol turnover and is mostly Mid2p dependent, suggesting that changes in cell turgor, mediated by intracellular accumulation of glycerol, are sensed by PKC sensors to promote the cell integrity response. These observations, together with previous results, suggest that yeast cells respond to changes in cellular turgor by remodeling their cell walls.